Transcutaneous medical devices are catheters, pins, implants and the like which pass through the skin and are indwelling for some considerable time. Exemplary of transcutaneous medical devices are central venous catheters, peripheral venous catheters, Swan-Gaus pulmonary catheters, central nervous system implants (ex. external ventricular drainage and ventricular reservoirs), peritoneal dialysis catheters, such as for continuous ambulatory peritoneal dialysis and continuous cyclic peritoneal dialysis, hemodialysis catheters, transvenous pacemaker leads and temporary orthopedic pins. All of these transcutaneous medical devices, when in place, have a portion of the device which is external, that is which is left protruding from the skin, and which can be the cause of infection.
The risk of acquiring infections from transcutaneous infections is very high. For instance, the risk of acquiring catheter-related bloodstream infection ranges from 0.9 to 8%. This nosocomial bloodstream infections cause a case fatality of more than 20%, and account for an increase of thousands of dollars in hospital costs per infection, or tens of thousands of dollars per survivor in ICU needing an extra week of hospital stay. As for peritoneal dialysis, a very experienced center today still has a peritonitis rate of one episode per 15 to 25 patient months. The major sources of bacteria in these infections are from surrounding skin.
To prevent infections associated with transcutaneous medical devices antiseptic preparation of insertion sites, including the initial application of topical anti-microbial solutions such as alcohol or iodine to the insertion sites is known. A further topical ointment after insertion of the device, such as an ointment containing neomycin, polymyxin and bactracin, has been shown to prevent catheter colonization/infection, but it may increase the risk of fungal infection. Ointments are also inconvenient, requiring multiple replacements. There have also been attempts to attach a cuff to the catheters, with an anti-microbial agent impregnated in the cuff. Efforts to coat the catheters with anti-microbial agents are known. However, none of these efforts has been completely successful in clinical trials. Presently, the most common catheter dressing used in hospitals comprises sterile gauze or polyurethane film, which have limited infection control properties.
Recent efforts to replace gauze with a transparent film dressing to allow a visual check on the insertion site is known, see for instance U.S. Pat. No. 5,372,589, issued Dec. 13, 1994 to Davis. No anti-microbial control is taught with such a dressing. Johnson & Johnson Medical Inc. markets a product under the trade mark BIOPATCH, which is a chlorhexidine gluconate-impregnated catheter patch. An Iodophor transparent dressing has also been suggested. However, to date, no completely effective anti-microbial device for use with transcutaneous medical devices is known.
A securement device is taught for securing an intravenous device to the body in U.S. Pat. No. 3,918,446, issued Nov. 11, 1975 to Buttaravoli. The device has an upper and a lower pad, between which the intravenous device is fixed. Since the function of the device is to secure the device to the body, there is a teaching to provide an adhesive material to the bottom of lower pad, and to the bottom of the top pad. There is a mention of providing the adhesive with an antibacterial agent. This device has the disadvantage of using adhesives with the antibacterial agent, which limits the effectiveness and long lasting ability of the antibacterial agent. Furthermore, the adhesive can be irritating next to the skin, cause skin damage and patient discomfort on removal, and inhibits the removal or changing of the device. Furthermore, many adhesives act as moisture barriers, which can limit the effectiveness of the antibacterial agent. Finally, the device of this patent teaches including a slit in the bottom pad of the dressing, which lies below the intravenous needle or catheter when the device is in place, allowing the intravenous device to remain in contact with the skin, and therefore limiting the infection control of the device.